(NOT APPLICABLE)
This invention relates generally to electric water heaters, and more particularly to electric water heaters for use in livestock water tanks exposed to low temperature extremes.
Livestock require large amounts of water throughout the year. In order to provide livestock with needed water during winter months, exterior livestock watering tanks are seasonally equipped with electric water heaters to prevent the water contained therein from icing over during cold temperatures. These heaters either float in the tank or rest on the bottom of the tank. The power cord extends from the heater and over the side wall of the tank for connection to a power outlet. Because the heater is not fixed in the tank in these prior designs, it is possible for the heater to be thrown from the tank when an animal drags on the power cord.
Commercially available water tanks typically include a drain opening in their side wall so that the tanks can be drained, e.g. for transporting or for putting in fresh water. It is desirable to have a tank heater in which the power cord extends from the tank through the drain opening so that cord is out of reach of the livestock. However, the size of the drain plug opening varies depending on the manufacturer, and in many instances the drain openings are too small to permit the male plug of the power cord to be inserted through the opening. As a result, there is a need for a tank heater that can be mounted through a variety of sizes of drain plug openings without modifying the drain plug or the water heater.
An object of the present invention is to provide an electric heater for use in livestock watering tanks that reduces the likelihood of the heater being displaced from the tank.
Another object of the present invention is to provide an electric heater that can be used with a variety of different commercially available water tanks, wherein the power cord for the heater extends through the drain plug opening of the tank.
Still another object of the present invention is to provide an electric water tank heater that is low cost and economical to manufacture.
A further object of the present invention is to provide an electric water tank heater that is rugged and durable.
Still another object of the present invention is to provide an electric water tank heater that can be installed through drain plug openings of varying diameters.
Yet another object of the present invention is to provide an apparatus that permits an electric water tank heater to be installed through the drain plug openings of varying diameters.
These and other objects are addressed by an apparatus for mounting an electric water heater through the drain plug opening of a water tank. The water heater includes a submersible electric heating element, a power cord having a first end electrically connected to the heating element and a second end interconnected with the heating element for delivering power thereto. The apparatus includes a drain plug adapter mounted about the power cord and being configured for installation through the drain plug opening to seal the drain plug opening against water leakage therethrough.
According to one embodiment, the drain plug adapter comprises a connector portion mounted about the power cord. The connector portion may be removably mounted on the power cord. In this embodiment, the connector portion may comprise first and second portions that are configured to clamp around the power cord. Alternatively, the connector portion may be permanently secured about the power cord. In this embodiment, the connector portion may be integrally formed with the housing of the submersible heating element. The connector portion has a first portion that is larger than the drain plug opening and a threaded boss extending from the first portion and being sized for insertion through the drain plug opening. A nut is threadable on the boss for securing the connector portion within the drain plug opening. A seal adapted to seal the drain plug opening around the boss to prevent water leakage therethrough.
According to another aspect of the present invention, the power cord may include a detachable connector interposed between the heating element and the male plug such that the power cord can be separated for insertion through the drain plug opening. The detachable connector can be positioned anywhere along the length of the power cord, and may have a portion that is integrally formed with the male plug, or the housing of the heater.
The heater includes a temperature control device interconnected between the power cord and the heating element for regulating power to the heating element to maintain the temperature of the contents of the tank within a preselected range. The interconnection between the heating element, the temperature control device and the power cord is contained within a hermetically sealed housing.